Medical injection apparatus

ABSTRACT

An injection apparatus includes components that facilitate injection of relatively viscous materials into a patient. An injection apparatus may include a transition-bore needle apparatus, which has a proximal end, a distal end, and a lumen extending from the proximal end to the distal end, in which the diameter of the proximal end is greater than the diameter of the distal end. An injection apparatus may include a hand-held injection facilitation apparatus, which may be coupled to a syringe. The hand-held injection facilitation apparatus can include a pivot arm and a body with a rod disposed within the body and coupled to the pivot arm. Movement of the pivot arm results in a proximal or distal movement of the rod within the body to effectively cause material to be expelled from the syringe. An injection apparatus may include a transition-bore needle apparatus and a hand-held injection facilitation apparatus in combination.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. ProvisionalApplication No. 60/298,310, entitled INJECTION FACILITATION APPARATUS,and filed Jun. 14, 2001; and U.S. Provisional Application No.60/298,620, entitled TRANSITION-BORE NEEDLE APPARATUS, and filed Jun.14, 2001, the entire contents of which are hereby incorporated byreference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates generally to medical devices and,more particularly, to injection apparatus that facilitate and improvethe ability to pass viscous materials through lumens of small aperture.

[0004] 2. Description of Related Art

[0005] The term “stress urinary incontinence” refers to a functionallyinsufficient urinary tract of a patient. In a patient having thiscondition, the tissue relaxation of the sphincter mechanism, located atthe urinary outflow of the bladder into the urethra, can cause a loss ofbladder control. Cystoscopes are typically used to study the urethra andbladder and to evaluate, for example, a patient's urinary incontinencecondition. A typical cystoscope may comprise a tubular instrumentequipped with, for example, a visual channel and a working channel, andconstructed to be inserted through the urethra for viewing of theurethra and bladder.

[0006] Treatment of a urinary incontinence condition may comprise theinjection of a filler material, such as collagen, into and adjacent tothe urinary sphincter muscle at the bladder neck, to thereby bulk up thetissue and assist in the adequate closure of the urinary sphincter.

[0007] Acid reflux is a digestive disorder which similarly involves thetissue relaxation of a sphincter mechanism. In the case of acid reflux,which is commonly known as gastroesophageal reflux disease (GERD) orheartburn, the lower esophageal sphincter connecting the esophagus tothe stomach begins to malfunction.

[0008] During proper operation of the lower esophageal sphincter, thelower esophageal sphincter opens to allow food to pass into the stomachand closes to prevent food and acidic stomach fluids from flowing backup into the esophagus. Gastroesophageal reflux occurs when the loweresophageal sphincter is weak or relaxes inappropriately, allowing thestomach's contents to retrograde or flow up into the esophagus.

[0009] This retrograde flow of gastric contents back into the esophagus,through what should be a one-way valve into the stomach, can damage theesophagus. More particularly, the contents of the stomach are veryacidic; and the lining of the stomach is specially designed to cope withthe lower pH contents. The esophagus, on the other hand, is not suitedfor such exposure to highly acidic materials. Thus, when acidretrogrades from the stomach into the esophageal tissues, irritation andinflammation will often result to these tissues.

[0010] The severity of tissue damage which can result fromgastroesophageal reflux disease can depend on factors such as thedysfunctional level of the lower esophageal sphincter, the type andamount of fluid brought up from the stomach, and the neutralizing effectof the patient's saliva.

[0011] Another factor, which may affect the severity of a particulargastroesophageal reflux disorder, is the patient's esophageal motility.Lack of esophageal motility can occur through either of two mechanisms.When incomplete emptying of the esophagus into the stomach afteringestion of liquids or solids occurs, the motility of the esophagus canbe said to be affected, resulting in esophageal reflux. Also, esophagealreflux can occur when small amounts of gastric contents, which may berefluxed into the lower esophagus, are not rapidly emptied back into thestomach. Delays in the emptying of this material, caused by anesophageal motility disorder, for example, can lead to irritation of theesophageal mucosa and possibly to the sensation of heartburn or thedevelopment of esophagitis.

[0012] Various tools and instruments have been used in the prior art forthe treatment of urinary incontinence and acid reflux disease.Gastroscopes are typically used to study the esophagus and to evaluate,for example, a patient's acid reflux condition. A gastroscope typicallycomprises a flexible, lighted instrument that is inserted through themouth and esophagus to view the stomach. Similarly, a cystoscope istypically inserted through a patient's urethra to facilitate evaluationof, for example, a urinary incontinence condition.

[0013] Treatment of either of the above-mentioned disorders may includeone or more injections of a viscous material, such as collagen, into thevicinity of either the lower esophageal sphincter (for treating acidreflux) or the sphincter of the urethra (for treating urinaryincontinence). These injection procedures typically involve elongatecatheters for the delivery of viscous materials through the bodypassages and to the target sites of injection. The force required todeliver a viscous material through the delivery lumen of an elongatecatheter will naturally increase as the length of the elongate catheterincreases. Moreover, the types of elongate catheters used with thesesurgical procedures will typically have delivery lumens of relativelysmall cross-sectional areas, thus further augmenting the force requiredto deliver the viscous material through the length of the elongatecatheter.

[0014] To compensate for the greater required force, it would bedesirable to form the elongate catheter to have a lumen with arelatively large cross-sectional area to facilitate flow of the viscousmaterial therethrough. Another design criterion is that the diameter ofthe needle tip should be relatively small to reduce tissue trauma at theinjection site, to increase precision in some instances, and to reducepatient discomfort.

[0015] In order to meet the objectives of both a relatively largedelivery lumen and a relatively small needle tip, a juncture must beformed at some point along the length of the needle to transition theneedle diameter from a relatively large size to a relatively small size.If the transition point is abrupt or too great in magnitude, optimalflow of the viscous material through the needle may be inhibited.

SUMMARY OF THE INVENTION

[0016] An injection apparatus, as disclosed herein, may comprise atransition-bore needle apparatus to optimize the flow of viscousmaterial from the injection apparatus. An injection apparatus, asdisclosed herein, may comprise a hand-held injection facilitationapparatus which reduces the effort required to displace viscous materialfrom the injection apparatus. The hand-held injection facilitationapparatus is structured to cooperatively interact with a syringe tocause displacement of viscous material from the syringe. An injectionapparatus may comprise a combination of a transition-bore needleapparatus, and a hand-held injection facilitation apparatus, disclosedherein.

[0017] A transition-bore needle apparatus is provided to optimize theflow of a viscous material through a decreasing-diameter lumen of aneedle. The transition-bore needle apparatus comprises a proximal endand a distal end, and the lumen extends from the proximal end of thetransition-bore needle apparatus to the distal end of thetransition-bore needle apparatus. A diameter at a proximal portion ofthe transition-bore needle apparatus is greater than a diameter at adistal portion of the transition-bore needle apparatus.

[0018] In accordance with one aspect of the present invention, theproximal portion of the transition-bore needle apparatus comprises afirst needle having a first diameter, and the distal portion of thetransition-bore needle apparatus comprises a second needle having asecond diameter. The first diameter is greater than the second diameter.The first needle comprises a proximal end, a distal end, and a firstlumen extending through the first needle from the proximal end to thedistal end, and the second needle similarly comprises a proximal end, adistal end, and a second lumen extending through the second needle fromthe proximal end of the second needle to the distal end of the secondneedle.

[0019] The lumen of the transition-bore needle apparatus comprises botha portion of the first lumen of the first needle and a portion of thesecond lumen of the second needle. A juncture thus exists within thelumen of the transition-bore needle apparatus, where the diameterthereof transitions from the first diameter to the second diameter. Atthis juncture, the proximal end of the first needle terminates withinthe second lumen. In accordance with an aspect of the present invention,the proximal end of the first needle is beveled to improve a flow ofviscous material through the lumen of the transition-bore needleapparatus. In accordance with another aspect of the present invention,the proximal end of the first needle is chamfered to improve a flow ofviscous material through the lumen of the transition-bore needleapparatus. According to yet another aspect of the present invention, theproximal end of the first needle is both chamfered and beveled toimprove a flow of viscous material through the lumen of thetransition-bore needle apparatus.

[0020] The transition-bore needle apparatus of the facilitates theinjection of viscous filler material by optimizing a flow of the viscousmaterial through the lumen of the transition-bore needle apparatus. Thetransition-bore needle apparatus may be used in conjunction withsurgical instruments, such as endoscopes, cystoscopes, and gastroscopes,to aid in intraluminal injections of materials into body tissues withinbody lumens. When the body lumen comprises an esophagus, the gastroscopeis inserted through the esophagus into a vicinity of the loweresophageal sphincter, and a long needle is used to inject a fillermaterial into and adjacent to the lower esophageal sphincter tissues forthe treatment of acid reflux. When the body lumen comprises a femaleurethra, the cystoscope is inserted through the urethra to the urinarysphincter adjacent to the bladder neck, and a long needle is used toinject a filler material into and adjacent to the urinary sphinctertissues for the treatment of stress urinary incontinence. The fillermaterial may also be injected, for example, along a greater length ofthe urethra.

[0021] The injection apparatus disclosed herein thus facilitates theinjection of viscous filler materials, and may provide for increasedspeed, accuracy and efficiency in dispensing such materials. Theinjection of bulking agents into the respective tissues of bodysphincters helps fortify the respective tissue structures andre-establish normal sphincter control. The transition-bore needleapparatus of the injection apparatus and associated methods of operationdisclosed herein may be configured for and used on other body passagesand tissues (e.g., wrinkles) as well in modified embodiments.

[0022] An injection apparatus may comprise a hand-held injectionfacilitation apparatus to increase the precision of dispensing of amaterial from a syringe. The injection facilitation apparatus may beused in conjunction with surgical instruments, such as endoscopes,cystoscopes, and gastroscopes, to aid in transurethral injection forintraluminal injections of materials into body tissues, and to visualizetissue within a body lumen. When the body lumen comprises an esophagus,the gastroscope is inserted through the esophagus into a vicinity of thelower esophageal sphincter, and a long needle is used to inject a fillermaterial into and adjacent to the lower esophageal sphincter tissues forthe treatment of acid reflux. When the body lumen comprises a femaleurethra, the gastro cystoscope is inserted through the urethra into theurinary sphincter adjacent to the bladder neck, and a long needle isused to inject a filler material into and adjacent to the urinarysphincter muscle tissues for the treatment of stress urinaryincontinence. The filler material may also be injected, for example,along the entire length of the urethra.

[0023] The hand-held injection facilitation apparatus of the injectionapparatus facilitates the injection of the viscous filler materials, andprovides for increased accuracy in dispensing such materials. Theinjection of a urinary bulking agents into the respective tissues ofbody sphincters helps fortify the respective tissue structures andre-establish normal bladder sphincter control. The apparatus of thepresent invention and associated methods of operation disclosed hereinmay be configured for and used on other body passages as well inmodified embodiments.

[0024] In accordance with one aspect of the present invention, aninjection facilitation apparatus is constructed for use in conjunctionwith a stainless steel needle tip catheter that can be introduced into apatient's urethra or esophagus in a treatment for urinary incontinenceor gastro-esophageal reflux. The treatment for gastro-esophageal refluxdisease may be fashioned to increase the strength or the length of thelower esophageal sphincter (LES) by depositing a viscous material aroundthe lower esophageal sphincter. The suspension can be injected via asyringe and needle directly into the specific areas where the viscousagent is desired. A principal use of the exemplary embodiment is toaccurately dispense the viscous material to thereby alter thephysiological architecture of the patient's sphincter and adjacenttissues. Thus the bio-mechanical characteristics of the sphincter andsurrounding tissues are altered to alleviate urinary incontinence andgastro-esophageal reflux.

[0025] The subjects and objects of this disclosure relate to novelmethods and instruments for facilitating the controlled dispensing ofviscous material in the interior of the body, including but not limitedto soft tissues, and lumen structures (e.g., esophagus, urethra).

[0026] The present invention, together with additional features andadvantages thereof, may best be understood by reference to the followingdescription taken in connection with the accompanying illustrativedrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0027]FIG. 1 illustrates a transition-bore needle apparatus for use inthe treatment of urinary incontinence in accordance with the presentinvention;

[0028]FIG. 1A is a cross-sectional view of a proximal end of a distalneedle with edges beveled at about a 45 degree angle from thelongitudinal axis of the distal needle;

[0029]FIG. 1B is a cross-sectional view of a proximal end of a distalneedle with edges chamfered at about a 45 degree angle from thelongitudinal axis of the distal needle;

[0030]FIG. 2 illustrates a transition-bore needle apparatus for used inthe treatment of gastro-esophageal reflux disease in accordance with thepresent invention;

[0031]FIG. 2A is a cross-sectional view of a proximal end of a needlewith edges chamfered at about a 30 degree angle from the longitudinalaxis of the needle;

[0032]FIG. 2B is a cross-sectional view of a proximal end of a needlewith edges beveled at about a 30 degree angle from the longitudinal axisof the needle;

[0033]FIG. 3 illustrates an injection facilitation apparatus with anattached syringe for use with a transition-bore needle apparatus;

[0034]FIG. 4 shows a part cross-sectional view of the injectionfacilitation apparatus, showing the housing and its internal components;

[0035]FIG. 5 is a part cross-sectional view of the injectionfacilitation apparatus wherein the handle is in a neutral position withno external force being applied to the handle;

[0036]FIG. 5A is a side-elevational view of the housing of the injectionfacilitation apparatus of FIG. 5, taken along the line A-A of FIG. 5;

[0037]FIG. 5B is a side-elevational view of an internal end of the pivotarm of the injection facilitation apparatus of FIG. 5, taken along theline B-B of FIG. 5;

[0038]FIG. 6 is a part cross-sectional view of the injectionfacilitation apparatus of FIG. 5 after an initial application ofexternal force has been applied to the handle;

[0039]FIG. 7 illustrates the injection facilitation apparatus of FIG. 5at a time of maximum application of external force to the handle; and

[0040]FIG. 8 illustrates a gastroscope used in the urethra to treaturinary incontinence in accordance with the present invention.

DETAILED DESCRIPTION OF THE PRESENTLY PREFERRED EMBODIMENTS

[0041] An injection apparatus that facilitates displacement of viscousmaterials from a catheter may comprise a transition-bore needleapparatus, a hand-held injection facilitation apparatus, or acombination thereof. The transition-bore needle apparatus and thehand-held injection facilitation apparatus, as disclosed herein, canreduce the effort required by a person to displace the viscous materialfrom the injection apparatus. In general, the transition-bore needleapparatus can reduce the effort required to expel material from acatheter by graduating changes of the internal diameter of the lumens ofcatheters. The hand-held injection facilitation apparatus can reduce theeffort required to expel material from a catheter by permitting a personto control the longitudinal displacement of a syringe plunger using agripping action of the person's hand as compared to a digit actionbetween the person's thumb and fingers, as is conventionally practiced.

[0042] Referring more particularly to the drawings, FIG. 1 illustrates atransition-bore needle apparatus 7 adapted for use in applications suchas urethral injections, and having a distal needle 8, an intermediatetube 10, and a proximal tube 13. Transition-bore needle apparatus 7 isan element of an injection apparatus, as disclosed herein. It is to beunderstood that, as used herein, the term “proximal” means the end orpart nearest to the operator of the instrument and the term “distal”means the end or part furthest from the operator. Thus, the front end ofthe instrument that enters the body canal is the distal end.

[0043] The distal needle 8 comprises a proximal end 15, a distal end 17,and a lumen 19 extending from the proximal end 15 to the distal end 17.The distal end 17 of the distal needle 8 preferably comprises a cuttingedge needle tip, which is suitable for puncturing skin and other softtissues such as muscle tissue. In an alternative embodiment, the distalend 17 of the distal needle 8 may comprise a round point needle tip foruse in connection with more delicate surgical operations. Theintermediate tube 10 comprises a proximal end 22, a distal end 23, and alumen 26 extending from the proximal end 22 to the distal end 23. Theproximal tube 13 comprises a proximal end 29, a distal end 31, and alumen 33 extending from the proximal end 29 to the distal end 31.

[0044] As presently embodied, the distal needle 8, the intermediate tube10, and the proximal tube 13 all comprise surgical stainless steel, suchas 304 grade surgical stainless steel or 316 grade surgical stainlesssteel. In accordance with one embodiment of the present invention, atleast two needles (e.g., the distal needle 8 and the intermediate tube10) are attached from larger to smaller diameter so as to create atransitional cone to facilitate the movement of viscous bulkingmaterial, such as material containing suspended beads or micro-spheres,through the transition-bore needle apparatus in a direction from thelarger diameter tube to the smaller diameter needle. In the presentlypreferred embodiment, three needles (i.e., the distal needle 8, theintermediate tube 10 and the proximal tube 13) are attached, preferablyusing an adhesive 34, from larger to smaller diameters so as to create atransitional cone to facilitate the movement of viscous materialsthrough the transition-bore needle apparatus in a direction from thelarger diameter needle to the smaller diameter needles. Other modifiedembodiments may incorporate a greater number of needles.

[0045] The lumen of the transition-bore needle apparatus 7 comprisesboth a portion of the lumen 19 of the distal needle 8 and a portion ofthe lumen 26 of the intermediate tube 10, as can be seen in FIG. 1. Ajuncture thus exists within the lumen of the transition-bore needleapparatus 7, where the diameter thereof transitions from a diameter ofthe intermediate tube 10 to a diameter of the distal needle 8. At thisjuncture, the proximal end 15 of the distal needle 8 terminates withinthe lumen 26 of the intermediate tube 10.

[0046] In the illustrated embodiment, the distal needle 8 comprises aninner diameter of about 0.008 inches and an outer diameter of about0.016 inches. The distal needle 8 fits into the intermediate tube 10,which in the illustrated embodiment comprises an inner diameter of about0.020 inches and an outer diameter of about 0.028 inches. In thepresently preferred embodiment, the distal needle 8 protrudes distallyabout 3 mm from the intermediate tube 13.

[0047] The intermediate tube 10 fits into the proximal tube 13, which aspresently embodied comprises an inner diameter of about 0.50 inches, anouter diameter of about 0.032 inches, and a length of about 12 inches.The proximal tube 13 encloses the proximal end 22 of the intermediatetube 10. The proximal tube 13 preferably comprises three hypotubes,which may facilitate a tighter fit around the intermediate tube 10and/or greater rigidity of the proximal tube 13.

[0048] A tissue stop 31 is preferably disposed about the distal needle 8next to the distal end 23 of the intermediate tube 10. The tissue stop31 preferably comprises a diameter, which is about the same as thediameter of the proximal tube 13. In alternative embodiments, otherdiameters may be constructed. The tissue stop 31 preferably comprises acircular perimeter, but may have oval or rectangular perimeters inalternative embodiments. The tissue stop 31 preferably comprises apolymeric material, which is more flexible than, for example, stainlesssteel. In modified embodiments, the tissue stop 31 may comprise surgicalstainless steel.

[0049] An angle between a plane of the tissue stop 31 and a longitudinalaxis of the transition-cone needle assembly 7 is preferably less thanninety degrees and, preferably, less than about seventy-five degreesand, more preferably, about sixty degrees as shown in FIG. 1. Theorientation of the tissue stop 31 is preferably selected so that aplanar surface of the tissue stop will align longitudinally with theaxis of the particular lumen that is being treated. In other words, aplanar surface of the tissue stop 31 should rest flat on the surface ofthe tissue that is to be treated with the distal needle 8. The tissuestop 31 will help to prevent the needle from penetrating deeper into thetissue than is required or desired. A surgeon performing an injectionprocedure using, for example, a cystoscope or the device disclosed inU.S. patent application Ser. No. 09/825,484, entitled URETHRA SURGICALDEVICE, can view the tissue stop 31 for assistance in performing theinjection at the proper angle and at the proper depth.

[0050] In a modified embodiment of the apparatus, the tissue stop 31 maybe omitted so that only the difference in outer diameters between thedistal needle 8 and the intermediate tube 10 effectively operate as atissue stop. In yet another modified embodiment, the tissue stop can besecured about the intermediate tube 10, instead of being secured aboutthe distal needle 8, so that a distal planar surface of the tissue stopis flush with the distal end 23 of the intermediate tube 15.

[0051] According to another aspect of the present invention, theproximal end 22 of the intermediate tube 10 is beveled to improve a flowof viscous material through the lumen of the transition-bore needleapparatus 7. FIG. 1A is a cross-sectional view of a proximal end 22 withedges beveled at a 45 degree angle from the longitudinal axis of thedistal needle 8. The beveling may be performed by filing an initiallysquare outer edge to an angle less than ninety degrees and, preferably,less than sixty degrees, and more preferably, about forty-five degrees.After the proximal end 22 of the intermediate tube 10 is beveled, theintermediate tube 10 is then secured within the lumen 33 of the proximaltube 13, through the application of adhesive material between the outersurface of the intermediate tube 10 and inner surface of the proximaltube 13 at their contacting surfaces. In modified embodiments, the anglemay be reduced to, for example, 30 degrees or even about 15 degrees fromthe longitudinal axis of the intermediate tube 10.

[0052] In accordance with another aspect of the present invention, theproximal end 22 of the intermediate tube 10 is chamfered to improve aflow of viscous material through the lumen of the transition-bore needleapparatus 7. FIG. 1B is a cross-sectional view of a proximal end 22 withedges chamfered at a 45 degree angle from the longitudinal axis of thedistal needle 8. The chamfering may be performed by filing an initiallysquare edge on the interior side of the tubing to an angle less thanninety degrees and, preferably, less than sixty degrees, and morepreferably, about forty-five degrees. In modified embodiments, the anglemay be reduced to, for example, 30 degrees, or even about 15 degreesfrom the longitudinal axis of the distal needle 8.

[0053] In yet another aspect of the present invention, the proximal end22 of the intermediate tube 10 is both chamfered and beveled, inaccordance with the structures discussed in the preceding paragraphs, tothereby improve a flow of viscous material through the lumen of thetransition-bore needle apparatus 7. The proximal end 15 of the distalneedle 8 is preferably beveled and/or chamfered, similarly to thatdescribed above in connection with the proximal end 22 of theintermediate tube 10. In modified embodiments, only the proximal end 15of the distal needle 8 is beveled and/or chamfered, and the proximal end22 of the intermediate tube 10 is neither beveled nor chamfered.

[0054] Turning now to FIG. 2, a transition-bore needle assembly 37 isillustrated for use in applications such as lower esophageal injectionsof bulking material. The transition-bore needle assembly 37 comprises aneedle 39 connected to a flexible tube 40. The flexible tube 40 maycomprise a polymeric material, such as polyethylene terephthalate (PET).The needle 39 comprises a proximal end 42, a distal end 44, and a lumen47 extending between the proximal end 42 and the distal end 44. Thedistal end 44 of the needle 44 preferably comprises a cutting edgeneedle tip, which is suitable for puncturing skin and other soft tissuessuch as muscle tissue. As presently embodied, the cutting edge needletip is formed at a 20 degree angle from a longitudinal axis of theneedle 39. In an alternative embodiment, the distal end 44 of the needle39 may comprise a round point needle tip. The flexible tube 40 similarlyhas a proximal end 49, a distal end 51, and a lumen 53 extending fromthe proximal end 49 to the distal end 51.

[0055] As presently embodied, the needle 39 comprises surgical stainlesssteel, such as 304 grade surgical stainless steel or 316 grade surgicalstainless steel. The proximal end 42 of the needle 39 is inserted intoand attached to the distal end 51 of the flexible tube 40, so as tocreate a transitional cone to facilitate the movement of viscous bulkingmaterial, such as material containing suspended beads or micro-spheres,through the transition-bore needle apparatus 37 in a direction from theflexible tube 40 to the needle 39. The lumen of the transition-boreneedle apparatus 37 comprises both a portion of the lumen 47 of theneedle 39 and a portion of the lumen 53 of the flexible tube 40, as canbe seen from FIG. 2. A juncture thus exists within the lumen of thetransition-bore needle apparatus 37, where the diameter thereoftransitions from a diameter of the flexible tube 40 to a diameter of theneedle 39. At this juncture, the proximal end 42 of the needle 39terminates within the lumen 53 of the flexible tube 40.

[0056] In the illustrated embodiment, the needle 39 has an innerdiameter of about 0.012 inches and an outer diameter of about 0.020inches, and the flexible tube 40 has an inner diameter of 0.032 inchesand an outer diameter of 0.056 inches. A wire 60 is wrapped around theneedle 39 and glued into place. In the gluing process, the glue 38 ispreferably allowed to dry and then heat cured. Another glue is thenapplied to the surfaces of the resulting wire 60 and needle 39. The gluemay comprise, for example, a lock-tight glue or a superglue. The needle39 is then gripped and held with, for example, a chuck, and screwed intothe flexible tube 40, which may comprise a polymeric tube having, forexample, a smooth inner surface. Some glue will remain on the distal end51 of the flexible tube 40 to form a seal, after the needle 39 and wire60 are screwed in. The wire 60 around the needle 39 preferably deformsthe smooth inner surface of the flexible tube 40 for a frictional fit.

[0057] According to another aspect of the present invention, theproximal end 42 of the needle 39 is beveled to improve a flow of viscousmaterial through the lumen of the transition-bore needle apparatus 37.FIG. 2A is a cross-sectional view of a proximal end 42 with edgeschamfered at about a 30 degree angle from the longitudinal axis of thedistal needle 39. The beveling may be performed by filing an initiallysquare edge to an angle less than ninety degrees and, preferably, lessthan sixty degrees, and more preferably, about forty-five degrees. Afterthe proximal end 42 of the needle 39 is beveled and/or chamfered, theneedle 39 is secured within the lumen 53 of the flexible tube 40. Inmodified embodiments, the angle may be reduced to, for example, 30degrees or about 15 degrees.

[0058] In accordance with another aspect of the present invention, theproximal end 42 of the needle 39 is chamfered to improve a flow ofviscous material through the lumen of the transition-bore needleapparatus 37. FIG. 2B is a cross-sectional view of a proximal end 42with edges chamfered at about a 30 degree angle from the longitudinalaxis of the distal needle 39. The chamfering may be performed by filingan initially square edge to an angle less than ninety degrees and,preferably, less than sixty degrees, and more preferably, aboutforty-five degrees. In modified embodiments, the angle may be reducedto, for example, 30 degrees, or even about 15 degrees. According to yetanother aspect of the present invention, the proximal end 42 of theneedle 39 is both chamfered and beveled, in accordance with thestructures discussed in this preceding paragraph, to thereby improve aflow of viscous material through the lumen of the transition-bore needleapparatus 37.

[0059]FIG. 3 illustrates an injection facilitation apparatus 17 for usewith the injection apparatus of the present invention. Injectionfacilitation apparatus 17 may be used with the transition-bore needleapparatus disclosed hereinabove. The housing 130 preferably comprises amolded polymeric material, generally in the shape of a hollow cylinder.In modified embodiments, other materials and shapes may be used. In theillustrated embodiment, the housing 130 comprises a proximal end 142, adistal end 144, a first side 139 and a second side 153.

[0060]FIGS. 4 and 5 are additional views of the injection facilitationapparatus 17. A portion of the housing 130 is preferably removed on thefirst side to accommodate a syringe 140 therein. In modifiedembodiments, other means, such as a hinged door, may be incorporated foraccommodating the syringe 140 into the housing 130. The housing 130comprises a slot 133, extending in a direction from the first side tothe second side into the housing and being configured to accommodate andhold a finger rest 134 of the syringe 140 within the housing. An endview of the housing 130, taken in the direction of the arrow A-A of FIG.5, is shown in FIG. 5A. A slot 138 is disposed at the distal end 144 ofthe housing 130 for accommodating the syringe 140 therein. The slot 138extends from the first side 139 of the housing in a direction toward thesecond side 153, and terminates with a circular or rounded portion 143for accommodating and holding the syringe 140.

[0061] A movable rod 113 extends within the housing 130 from theproximal end 142 to the distal end 144 (in accordance with a fullyextended position of the rod 113). When the rod 113 pushes distallyagainst the syringe 140, the syringe 140 will tend to move in the distaldirection. The finger rest 134 of the syringe 140, however, will pressdistally against the slot 133, to thereby prevent distal movement of thesyringe 140. Thus, only the plunger 136 of the syringe 140 will movedistally under the distal force of the rod 113. Distal movement of theplunger 136, relative to the rest of the syringe 140, will result in theplunger 136 expelling a portion of the syringe contents, which maycomprise a viscous bulking agent, from the syringe 140 and into theelongate catheter 141.

[0062] The elongate catheter 141 preferably comprises a lengthsufficient to extend through the relevant body passage and to the siteof operation. For example, the elongate catheter 141 may be constructedto have a length sufficient to extend through a cystoscope for operationon the urinary sphincter near the bladder. As another example, theelongate catheter 141 may be configured to have a length (e.g., aboutone meter) sufficient to extend through a gastroscope for operation onthe lower esophageal sphincter near the stomach. The elongate catheter141 may comprise or be connected to the flexible tube 13 of FIG. 1 orthe proximal tube 40 of FIG. 2.

[0063] The force required for delivery of a viscous fluid through theelongate catheter 141 and to the target site of injection will beproportionate to the length and cross-sectional area of the elongatecatheter 141. This force required to deliver the viscous materialthrough the lumen of the elongate catheter will thus increase as thelength of the elongate catheter increases, and further will increase asthe cross-sectional area of the elongate catheter is decreased.

[0064] The injection facilitation apparatus 17 of the present inventionfacilitates the injection of viscous filler materials, and provides forincreased accuracy in the amounts of such dispensed materials. Anexemplary embodiment of the invention comprises an injectionfacilitation apparatus for use in conjunction with a needle tipstainless steel elongate catheter that can be introduced through apatient's urethra in the treatment of urinary incontinence. As anotherexample, a treatment for gastro-esophageal reflux disease may befashioned to increase the strength or length of the lower esophagealsphincter (LES) via the deposition of a viscous bulking material intosurrounding tissues of the lower esophageal sphincter. An injectionfacilitation apparatus of the present invention is suitable for such usein conjunction with a needle tip, flexible, polymeric elongate catheter.The viscous suspension can be injected via a syringe and needle directlyinto the specific areas where the viscous agent is desired. Principaluses of the present invention are to accurately and convenientlydispense the viscous material to thereby alter the operationalarchitecture of the patient's sphincter. Thus, the bio-mechanicalcharacteristics of the sphincter are altered to alleviate the disorder.

[0065] As shown in FIG. 3, a fastener 128 comprises an aperture foraccommodating the rod 113 therethrough, and is biased proximally againstan inner surface of the proximal end 142 of the housing 130. In theillustrated embodiment, the fastener 28 comprises surgical stainlesssteel. A handle spring 122 is disposed about the rod 113 between aninternal end 110 of a pivot arm 18 and the fastener 128. In addition tocomprising an internal end 110, the pivot arm 18 further comprises ahandle end 111. The handle spring 122 provides a proximal biasing forceagainst the fastener 128 and a distal biasing force against the internalend 110 of the pivot arm 8. The handle spring 122 may comprise, forexample, surgical stainless steel.

[0066] It can be seen from the figure that the handle spring 122 biasesan internal first end 110 a of the pivot arm 18 distally, and thedriving spring 119 biases an internal second end 110 b of the pivot arm18 proximally. The combination of the handle spring 122 and the drivingspring 119 tend to rotate the pivot arm 18 about the pivot pin 132 inthe clockwise direction shown by the arrow A1. An inward thrust by thehand of a user on the handle end 111 of the pivot arm 18 causes thepivot arm 18 to rotate about the pivot pin 132 in the direction of thearrow A2. As the pivot arm 18 pivots about the pivot pin 132, theinternal first end 110 a of the pivot arm 18 moves generally in aproximal direction and the internal second end 110 b of the pivot arm 18moves generally in a distal direction. When the internal second end 110b of the pivot arm 18 moves distally in response to the handle end 111moving in the direction of the arrow A2, the screw head 115, which issecured to the internal second end 110 b, applies a distal force againstthe biased end 126 of the of the driving arm 116.

[0067] In the illustrated embodiment, the handle end 111 is attached tothe internal end 110 via two small identical screws 150 (FIG. 5), andthe internal end 110 rests on the handle spring 122. As can be seen bestin FIG. 3, a pivot pin 132, preferably comprising a surgical stainlesssteel bar, passes through both the housing 130 and the internal end 110of the pivot arm 18. The pivot arm 18 thus pivots about the pivot pin132 in both clockwise and counter-clockwise directions, as shown in FIG.3 by the arrows A1 and A2, respectively.

[0068] A ring 112, which preferably comprises surgical stainless steel,is disposed around the rod 113 between the internal end 110 and adriving arm 116. The ring 112 preferably comprises a loosely fitted andmovable stainless steel washer. The driving arm 116, preferablycomprising stainless steel, rests on top of the ring 112. In between thedriving arm 116 and the internal end 110 also rests a screw head 115,positioned on a distal side of the internal end 110. The screw head 115is secured onto the internal end 110 of the pivot arm 18 with a nut 121,as can be seen from FIG. 5b. Distally of the driving arm 116 rests thedriving spring 119, which is held in place by an alignment protrusion151 that preferably comprises a knob (not shown) formed on a housingwall 155 of the housing 130

[0069] The rod 113 extends through the fastener 128, the handle spring122, the pivot arm 18, the ring 112, and driving arm 116. The internalend 110 of the pivot arm 18 and the driving arm 116, in combination withthe fastener 128, work together to provide slidable alignment to the rod113. The rod 113 comprises a proximal rod disk 137 connected at aproximal end of the rod 113 and a distal rod disk 135 connected at adistal end of the rod 113. As presently embodied, the rod 113 isremovably attached to at least one of the proximal rod disk 137 and thedistal rod disk 135. In the illustrated embodiment, the rod 113 ispermanently secured to or integrally formed with the proximal rod disk137 and is removably connected (e.g., threaded) to the distal rod disk135.

[0070] The injection facilitation apparatus 17 contains a pivotmechanism that forces the rod 113 distally within the housing 130 towardthe slot 133, where the syringe 140 is held and positioned, asillustrated in FIG. 3. A clear depiction of the slot 133 can be seen inFIG. 4. When the syringe 140 is positioned within and held by thehousing 130, a base of the syringe, plunger 136, rests flat against thedistal rod disc 135.

[0071] FIGS. 3-5 depict the injection facilitation apparatus 17 at rest,wherein no external force is applied to the handle end 111 of the pivotarm 18. In the relaxed or resting position of FIGS. 3-5, there is no gapbetween the driving arm 116 and the ring 112, which rests on theinternal end 110 of the pivot arm 18. It can be seen from the figurethat without an external force applied to the handle end 111 of thepivot arm 18, the internal end 110 of the pivot arm 18 rests between thehandle spring 122 and a combination of the ring 112 and the driving arm116. The handle spring 122 biases an internal first end 110 a of thepivot arm 18 distally, and the driving spring 119 biases an internalsecond end 110 b of the pivot arm 18 proximally.

[0072] The combination of the handle spring 122 and the driving spring119 tend to rotate the pivot arm 18 about the pivot pin 32 in theclockwise direction shown by the arrow A1. However, in accordance withan aspect of the present invention, a rotation-limiting structureprevents the pivot arm 18 from rotating clockwise past the orientationshown in FIG. 3 and FIG. 5. For this reason, the orientation of thepivot arm 18 shown in, for example, FIG. 3 is referred to as being inthe relaxed position. Application of a force by the hand of an operatorto pivot the handle end 111 of the pivot arm 18 in the counter-clockwisedirection shown by arrow A2 will move the assembly out of the relaxedposition and move the rod 113 distally.

[0073] Regarding the rotation-limiting structure and with reference toFIG. 5, the handle spring 122 applies a distal force onto the internalfirst end 110 a, resulting in the generation of a rotational force ormoment arm on the internal end 110 which would cause the internal end110 to rotate about the pivot pin 132 in the direction of the arrow A1.If the pivot pin 132 were to rotate in the direction of the arrow A1,the internal first end 110 a would pivot distally about the pivot pin132 and the internal second end 110 b would pivot proximally about thepivot pin 132. When the internal end 110 of the pivot arm 18 is in theresting position as shown in FIGS. 3-5, however, an aperture 123, whichis disposed on the internal end 110 of the pivot arm 18 foraccommodating the rod 113 therethrough, prevents rotation in thedirection of the arrow A1. An end view of the internal end 110, taken inthe direction of the arrow B-B of FIG. 5, is shown in FIG. 5B. Theaperture 123, which serves as a rotation-limiting structure, is shapedto (1) allow pivoting of the internal end 110 from the position shown inFIGS. 3-5 in the direction of the arrow A2, and (2) prevent pivoting ofthe internal end 110 from the position shown in FIGS. 3-5 in thedirection of the arrow A1.

[0074] More particularly, the aperture 123 comprises an elongate shapehaving a width that is about the same dimension as a diameter of the rod113 passing through the aperture 123, and having a length that isappreciably greater than the diameter of the rod 113 passing through theaperture 123. For example, the length should be at least 1.25 times thediameter of the rod 113 passing through the aperture 123 and,preferably, should be at least about 1.5 times, and more preferably,should be about 2 times the diameter of the rod 113 passing through theaperture 123.

[0075] Now, regarding the orientation of the aperture 123 relative tothe rod 113 passing therethrough, in the position shown in FIG. 5 theportion of the aperture 123 closest to the internal first end 110 a ofthe pivot arm 18 contacts the rod 113 to prevent further movement of thepivot arm 18 in the direction of the arrow A1. However, in the sameposition shown in FIG. 5, the portion of the aperture 123 closest to theinternal second end 110 b of the pivot arm 18 does not contact and isspaced from the rod 113 to facilitate movement of the pivot arm 18 inthe direction of the arrow A2. Thus, the engagement of the portion(e.g., edge) of the aperture 123 closest to the internal first end 110 awith the rod 113 serves to limit rotational movement of the pivot arm 18in the direction of the arrow A1. In modified embodiments, otherconstructions may be used to limit rotational movement of the pivot arm18 in the direction of the arrow A1, such as a protrusion on the secondside 153 of the housing 130 to contact the internal second end 10 b andprevent that end from moving proximally from the position shown in FIG.5.

[0076] The effect of a pivoting force applied by the hand of a user onthe pivot arm 18 of the injection facilitation apparatus 17 can be seenthrough a comparison of FIGS. 5-7. An inward thrust by the hand of auser on the handle end 111 of the pivot arm 18 causes the pivot arm 18to rotate about the pivot pin 132 in the direction of the arrow A2. Asthe pivot arm 18 pivots about the pivot pin 132, the internal first end110 a of the pivot arm 18 moves generally in a proximal direction andthe internal second end 110 b of the pivot arm 18 moves generally in adistal direction. When the internal second end 110 b of the pivot arm 18moves distally in response to the handle end 111 moving in the directionof the arrow A2, the screw head 115, which is secured to the internalsecond end 110 b, applies a distal force against the biased end 126 ofthe of the driving arm 116.

[0077] As the screw head 115 moves generally distally, while rotatingabout the pivot pin 132, the screw head 115 slides against the drivingarm 116 in a direction toward the rod 113. The component of movement ofthe screw head 115 in the distal direction, as it slides on the drivingarm 116, moves the biased end 126 of the driving arm 116 distallyagainst the proximal bias of the driving spring 119. The changes inposition of the pivot arm 18 and the driving arm 116 can be seen throughthe progression of FIGS. 5-7.

[0078] The initial distal movement of the screw head 115 is applied tothe biased end 126 of the driving arm 116, which generates a moment arm.The moment arm tends to cause the driving arm 116 to pivot generally inthe direction of the arrow A2 and generally about a pivot point definedby the interaction of the rod 113 and the driving arm 116.

[0079] A rod-clamping end 125 of the driving arm 116 comprises anaperture for accommodating the rod 113 therethrough. The cross-sectionalarea of the aperture is shaped to be slightly larger than thecross-sectional area of the rod 113, so that the rod 113 can freely movethrough the aperture when the driving arm 116 is oriented at apredetermined orientation (corresponding, for example, to an orientationwhen the pivot arm 18 is in the relaxed position). As presentlyembodied, the rod 113 can freely move through the aperture of thedriving arm 113, with little or reduced friction relative to otherorientations, when the driving arm 113 is substantially perpendicular toan axis of the rod 113. In modified embodiments, other angular positionsmay be implemented.

[0080] As the driving arm 116 moves under the influence of the screwhead 115 from its perpendicular orientation in an approximate directionof the arrow A2, biased end 126 of the driving arm 116 will moveslightly distally so that the orientation of the driving arm d116changes and so that the rod 113 can no longer freely slide (or slidewith reduced friction) through the aperture of the driving arm 116.Thus, the clamping end 125 of the driving arm 116 will be somewhatlocked onto the rod 113 at the angle of contact (which as presentlyembodied is an angle of about one to a about five degrees from 90degrees). At this position, shown in FIG. 6, there will be a small gapbetween internal end 110 and driving arm 116.

[0081] Further movement of the handle end 111 in the direction of thearrow A2 is depicted in FIG. 7. During this extended push on pivot arm18 the distance between internal end 110 and driving arm 116 willincrease to its maximum separation. The screw head 115 continues to movethe driving arm 116 distally. Since the driving arm 116 has alreadyrotated slightly to clamp the rod 113, the driving arm 116 will notrotate further as the screw head 115 pushes further and further distallyagainst the driving arm 116. Thus, continued movement of the screw head115 against the driving arm 116 moves the driving arm 116, which in turnmoves the clamped rod 113 forward.

[0082] As the driving arm 116 moves forward, the driving spring 119 iscompressed against the housing wall 155, and the handle spring 122 iscompressed proximally against the fastener 128 by proximal movement ofthe internal first end 110 a. In the illustrated embodiment, movement ofthe pivot arm 18 in the direction of the arrow A2 will cease when thehandle end 111 contacts the surface of the housing 130.

[0083] In modified embodiments of the invention the length of theinternal end 110 can be altered. Varying the length of the internal end110 can vary the amount of material expelled from the catheter-syringewithin the injection facilitation apparatus. For example, the internalend 110 can be lengthened such that the new added length protrudes outof the housing on the second side 153, which will cause a proportionalincrease in the range of movement of the handle end 111. In accordancewith another modification, the angle formed between the handle end 111and the internal end 110 can be increased so that the handle end 111 canbe moved further in the direction of the arrow A2 for a correspondinggreater movement of the rod 113. In accordance with one aspect of thepresent invention, the injection facilitation apparatus is engineered sothat a full compression of the handle end 111 will eject an exact amountof filler material, such as a specific volume amount to generate onemucosa bulge near a urinary sphincter.

[0084] As the angle between the handle end 111 and the internal end 110increases, the amount of distance created between the internal end 110and the driving arm 116 at maximum compression of the handle end 111 isalso intensified. This translates into a greater range of push movementon the rod 113, and thus a greater amount of viscous material beingexpelled from the syringe as the plunger 136 receives the additionalpush from the rod 113.

[0085] In other words, the screw head 115 moves generally distally, tothereby move the biased end 126 of the driving arm 116 distally againstthe proximal bias of the driving spring 119. The initial distal movementof the screw head 115 is applied to the biased end 126 of the drivingarm 116, which generates a moment arm. The moment arm tends to cause thedriving arm 116 to pivot generally in the direction of the arrow A2 andgenerally about a pivot point defined by the interaction of the rod 113and the driving arm 116. As the driving arm 116 moves under theinfluence of the screw head 115 from its perpendicular orientation in anapproximate direction of the arrow A2. The biased end 126 of the drivingarm 116 will move slightly distally so that the orientation of thedriving arm 116 changes and so that the rod 113 can no longer freelyslide (or slide with reduced friction) through the aperture of thedriving arm 116. Thus, the clamping end 125 of the driving arm 116 willbe somewhat locked onto the rod 113 at the angle of contact (which aspresently embodied is an angle of about one to a about five degrees from90 degrees). Continued movement of the screw head 115 against thedriving arm 116 moves the driving arm 116, which in turn moves theclamped rod 113 forward.

[0086] Although the injection facilitation apparatus 17 is designed tofacilitate accurate dispensing of viscous materials from a syringe, suchas filler materials, the injection facilitation apparatus 17 further maybe used to accurately dispense other materials and fluids as well. Inthe illustrated embodiment, the filler material comprises collagenand/or micro-spheres, such as disclosed in U.S. Pat. No. 5,344,452, thecontents of which are expressly incorporated herein by reference, or,for example, any other type of injectable bulking agent.

[0087] Another alternative embodiment would comprise a longer housing120, with a correspondingly longer rod 113, such that the length of therod 114 would extend proximally an additional distance equal to about alength of the handle end 111. The handle end 111 would then be attachedvia screws 150 to the internal end 110 in an inverted position, so thatthe handle end 111 extends proximally instead of distally. The handlecan be formed of another shape to accommodate the different direction ofaction, and the mechanism of action and other components would remainsubstantially the same.

[0088] The injection facilitation apparatus 17 can increase theprecision of dispensing fluids from the syringe 140, as it can becalibrated to permit a specific concentration of material to bedispensed from the syringe corresponding to a certain range of movementof the handle end 111. This is especially important due to the highlevel of viscosity of the material being passed through the syringe, thedistance of the elongate catheter 141, and the general need for surgicalprecision when injecting bulking agents. Further, the injectionfacilitation apparatus 17 can facilitate effective dispensation byreducing the amount of strength or effort required to secrete theviscous material out the syringe.

[0089] The treatment for gastro-esophageal reflux disease may befashioned to increase the strength or the length of the lower esophagealsphincter (LES) by depositing a viscous material around the loweresophageal sphincter. The suspension can be injected via a syringe andneedle directly into the specific areas where the viscous agent isdesired. A principal use of the exemplary embodiment is to accuratelydispense the viscous material to thereby alter the physiologicalarchitecture of the patient's sphincter and adjacent tissues. Thus thebio-mechanical characteristics of the and sphincter surrounding tissuesare altered to alleviate urinary incontinence and gastro-esophagealreflux.

[0090] The transition-bore needle apparatus 17 of the present inventionfacilitates the injection of the viscous filler material, by optimizinga flow of the viscous material at the junctions of the needles used forintraluminal injections. The transition-bore needle apparatus 17 may beused in conjunction with surgical instruments, such as endoscopes,cystoscopes, and gastroscopes, to aid in intraluminal injections ofmaterials into body tissues within body lumens. When the body lumencomprises an esophagus, the gastroscope is inserted through theesophagus into a vicinity of the lower esophageal sphincter, and a longneedle is used to inject a filler material into and adjacent to thelower esophageal sphincter tissues for the treatment of acid reflux.When the body lumen comprises a female urethra, the cystoscope isinserted through the urethra to the urinary sphincter adjacent to thebladder neck, and a long needle is used to inject a filler material intoand adjacent to the urinary sphincter tissues for the treatment ofstress urinary incontinence. The filler material may also be injected,for example, along a greater length of the urethra.

[0091]FIG. 8 illustrates a gastroscope 158 inserted through an esophagus159 of a patient. The gastroscope 158 is positioned near the patient'slower esophageal sphincter 164 just above the body of the stomach 166.The injection facilitation apparatus 17 of the present invention is usedin conjunction with a syringe and the gastroscope 158 of FIG. 8.

[0092] The gastroscope 158 in the illustrated embodiment is constructedto be flexible and to be capable of bending, for example, one hundredeighty degrees. Although other scopes and surgical devices suitable forinsertion and manipulation within body passages may be used inaccordance with the present invention, the presently illustratedsurgical device comprises a gastroscope 158 having a flexible, cylinderbody with a distal end 168 for facilitating surgical procedures within abody passage. In the illustrated embodiment, the gastroscope 158comprises an Olympus GIF-K Gastroscope.

[0093] The distal end 168 in the illustrated embodiment comprises fiveopenings, but as few as two openings may be incorporated in modifiedembodiments. An objective lens 160 is enclosed in a first one of theopenings to provide a visual pathway through the lumen and of thesurgical site of interest. The gastroscope 158 further comprises anotheropening for providing a suction and/or working channel 165. Alsoprovided at the distal end 168 is a channel for accommodating a lightguide 162, which carries light to the distal end 168 for facilitatingviewing of the treatment area through the visual passageway. The lightguide 162 preferably comprises a fiber optic light guide. Alternativelya LED, or other bulb, or other light source may be incorporated. Awater-feeding nozzle 169, which directs pressurized water across theobjective lens 160 to clear debris and an air-feeding nozzle 167 arealso housed within two respective channels of the gastroscope 158. Theair-feeding nozzle 167 can be used to direct pressurized air across theobjective lens 160 to remove moisture and to provide, in accordance withone application, distension of the cavity being examined.

[0094] An elongated catheter, such as that shown at 141 in FIG. 3, isinserted through the working channel 165 for dispensing a somewhatviscous material into the surgical site, which in FIG. 8 comprises avicinity of the lower esophageal sphincter 164. In the presentlypreferred embodiment, the elongate catheter 141 may have a length of,for example, about 1 meter to allow the elongate catheter to extendthrough the esophagus and to the lower esophageal sphincter 164.

[0095] The user presses the handle end 111 to thereby move the rod 113distally against the syringe plunger 136. Distal movement of the plunger136 forces viscous material within the syringe 140 distally out of thesyringe 140 and through the elongate catheter 141. The elongate catheter141 in the illustrated embodiment comprises a flexible material, such asa polymeric material, to facilitate maneuverability of the gastroscope158. When the elongate catheter 141 is used in connection with a urethraprocedure, such as the injection of bulking or filling material into avicinity of a urinary sphincter, the elongate catheter 141 preferablycomprises a surgical stainless steel. Injection procedures andapparatus, which utilize an elongate catheter and an accompanyingsyringe for treating, for example, urinary incontinence, and which aresuitable for use with the injection facilitation apparatus 17 forurethral applications, are described in co-pending U.S. application Ser.No. 09/825,484, entitled URETHRA SURGICAL DEVICE, filed Apr. 2, 2001,the contents of which are expressly incorporated herein by reference.

[0096] A needle 173 is disposed at a distal end of the elongate catheter141 for transferring viscous or other material from the elongatecatheter 141 into tissue. The needle 173 penetrates into the tissue nearthe lower esophageal sphincter to inject a bulge 175 of bulking agent,as shown in FIG. 8. Additional bulking agent injections are formedaround the lower esophageal sphincter 164 to thereby bulk up the tissuein the vicinity of the lower esophageal sphincter.

[0097] The needle preferably penetrates through the mucosa but notthrough the muscle layers of the lower esophageal sphincter 164, tothereby enable the injection of bulking material between these tissues.In modified embodiments, the needle may further be placed into thelayers of muscle of the lower esophageal sphincter to facilitate theinjection of bulking agent into these tissues as well. In urethralprocedures, the needle preferably penetrates through the mucosa but notthrough the muscle layers of the urinary sphincter, to therebyfacilitate the injection of bulking material between these tissues; andin modified embodiments, the needle is further inserted into the layersof muscle of the urinary sphincter to facilitate the injection ofbulking agent into these tissues as well. Uses of the injectionfacilitation apparatus 17 are not limited to the above examples; theinvention encompasses other foreseeable uses such as injections ofviscous or other materials through elongate catheters into the colon,vagina, vessels, and other lumen structures.

[0098] Although an exemplary embodiment of the invention has been shownand described, many other changes, modifications and substitutions, inaddition to those set forth in the above paragraphs, may be made by onehaving ordinary skill in the art without necessarily departing from thespirit and scope of this invention.

What is claimed is:
 1. An injection apparatus, comprising: atransition-bore needle apparatus, which comprises a proximal end, adistal end, and a lumen extending from the proximal end to the distalend, wherein a diameter of the proximal end of the transition-boreneedle apparatus is greater than a diameter of the distal end of thetransition-bore needle apparatus, wherein the proximal portion of thetransition-bore needle apparatus comprises a first needle having a firstdiameter, and distal portion of the transition-bore needle apparatuscomprises a second needle having a second diameter.
 2. The apparatus ofclaim 1, wherein the first needle is glued to the second needle.
 3. Theapparatus of claim 1, wherein the first diameter is greater than thesecond diameter.
 4. The apparatus of claim 1, wherein the first needlecomprises a proximal end, a distal end, and a first lumen extendingthrough the first needle from the proximal end to the distal end, andwherein the second needle comprises a proximal end, a distal end, and asecond lumen extending through the second needled from the proximal endof the second needle to the distal end of the second needle.
 5. Theapparatus of claim 1, wherein the transition-bore needle apparatuscomprises a portion of the first lumen of the first needle and a portionof the second lumen of the second needle, and a juncture in the lumen ofthe transition-bore needle apparatus, where the diameter thereoftransitions from the first diameter to the second diameter.
 6. Theapparatus of claim 5, wherein the proximal end of the first needleterminates within the second lumen, and where the termination is at thejuncture of the transition-bore apparatus.
 7. The apparatus of claim 1,wherein the proximal end of the first needle is beveled to improve flowof viscous material through the lumen of the transition-bore needleapparatus.
 8. The apparatus of claim 1, wherein the proximal end of thefirst needle is chamfered to improve a flow of viscous material throughthe lumen of the transition-bore needle apparatus.
 9. The apparatus ofclaim 1, wherein the proximal end of the first needle is beveled andchamfered to improve a flow of viscous material through the lumen of thetransition-bore needle apparatus.
 10. The apparatus of claim 1, furthercomprising a tissue stop disposed around a perimeter of thetransition-bore needle apparatus.
 11. An injection apparatus, comprisinga hand-held injection facilitation apparatus, which comprises a bodythat retains a syringe; a rod disposed in the body, the rod comprising adistal end that contacts a proximal end of a plunger of the syringe; anda pivot arm coupled to the rod and extending from the body so thatmovement of the pivot arm effects longitudinal displacement of theplunger of the syringe.
 12. The injection apparatus of claim 11, whereinthe body comprises a slot that accommodates a finger rest of thesyringe.
 13. The injection apparatus of claim 11, wherein the rodcomprises a proximal end that has a spring disposed therearound, thespring being disposed between a proximal end of the body and an end ofthe pivot arm.
 14. The injection apparatus of claim 11, wherein thepivot arm comprises an internal end disposed between two springs withinthe body, each of the springs providing opposing forces on the internalend of the pivot arm.
 15. The injection apparatus of claim 11, whereinthe rod has an end that extends from a proximal end of the body.
 16. Theinjection apparatus of claim 11, further comprising a transition-boreneedle apparatus coupled to the hand-held injection facilitationapparatus, wherein the transition-bore needle apparatus and thehand-held injection facilitation apparatus reduce the effort exerted bya person to eject a viscous material from the injection apparatus ascompared to a syringe and catheter combination without a transition-boreneedle apparatus and hand-held injection facilitation apparatus.
 17. Aninjection apparatus for dispensiong a viscous material, comprising atransition-bore needle apparatus, which comprises a needle at a distalend of the transition-bore needle apparatus, the needle having an outerdiameter, and a proximal and distal end; and at least one catheterhaving a distal end, the distal end of the at least one cathetersealingly attached to the proximal end of the needle so that fluid isdisplaced through a lumen of the catheter and a lumen of the needlewithout being displaced between the engagement of the catheter and theneedle; and a hand-held injection facilitation apparatus coupled to theat least one catheter, the hand-held injection facilitation apparatuscomprising a hollow body that retains a syringe that is attached to thecatheter; a longitudinally displaceable rod disposed within the body,wherein a distal end of the rod contacts a proximal end of a plunger ofthe syringe; and a pivot arm coupled to the rod and extending from thebody so that movement of the pivot arm causes longitudinal movement ofthe plunger of the syringe.
 18. The injection apparatus of claim 17,further comprising a tissue stop disposed around the transition-boreneedle apparatus so that the needle of the transition-bore needleapparatus is inserted a predetermined distance into a patient.
 19. Theinjection apparatus of claim 17, further comprising a plurality ofsprings disposed on opposite sides of an internal end of the pivot armto provide opposing forces to the internal end of the pivot arm.
 20. Theinjection apparatus of claim 17, further comprising a slot within thebody of the hand-held injection facilitation apparatus, the slotdimensioned to receive a finger rest of the syringe and to preventdistal displacement of the syringe from the hand-held injectionfacilitation apparatus.